It shall be unlawful for any milk dealer subject to the provisions of a marketing plan to handle milk subject to the provisions of such marketing plan without first obtaining an annual license from the director for each separate place of business where such milk is received or sold. Such license shall be in addition to any other license required by the laws of this state: PROVIDED, That the provisions of this section shall not become effective for a period of sixty days subsequent to the inception of a marketing plan in any marketing area prescribed by the director.